This study evaluated the pollutant levels (NO2, SO2, CO, and O3), air quality index (AQI) and the influence of meteorological variables and coronavirus disease (COVID-19) pandemic on the air quality in Rio de Janeiro. The data set used comprises periods before (March-April, 2019) and during pandemic (March-April, 2020). According to the AQI results, on most days, the air quality was ranked as “good”. Brazilian air quality standards for SO2, O3, and NO2 were not exceeded in any of the monitoring stations during partial lockdown, while CO exceeded in all periods in one site due to industrial emission. Comparing both periods, descriptive statistics for the meteorological parameters presented no differences, which suggests similar conditions. However, when evaluated week by week in 2020, weather conditions presented some differences that probably affected pollutant concentrations. The correlations between O3 and NO2 and some meteorological parameters indicate that variations in both favored ozone formation, since it is a photochemical process favored by temperature and solar radiation and that, in Rio de Janeiro, low NO2 concentrations lead to increased O3. The improvements on air quality during the partial lockdown may be attributed mainly to a reduction on emission sources rather than weather conditions.

The operational conditions of β-galactosidase encapsulated in pectin-alginate hydrogel were investigated as well as its catalytic activity in the hydrolysis of lactose from whey and whole milk. β-Galactosidase encapsulated in pectin-alginate hydrogel showed the best results to yields and diffusional effect and pH range. Thermostability showed considerable income gain for half-life (1.7-fold), activation energy of denaturation (31.6-fold), activation of denaturation (217.3-fold at 40 ºC; 266.8-fold at 50 ºC; 345.6-fold at 60 ºC), and entropy of activation of denaturation (-42.0 J mol 1 K-1). Reusability of encapsulated β-galactosidase was observed in 8-cycles for the milk whey lactose hydrolysis (51.9%) and 7-cycles for whole milk (55.6%), and the lactose hydrolysis was observed in 13% in milk whey and 10.3% in whole milk after 10 cycles. These results revealed an industrial application potential of β-galactosidase encapsulated in pectin-alginate hydrogel for lactose hydrolysis of milk whey and whole milk processes.

ABSTRACT Sugarcane is considered one of the main alternatives for biofuel production and an important product of Brazilian agriculture, so it is indispensable to adopt new techniques for its cultivation and management. Thus, the present study aimed to evaluate the effect of the quality of supplemental lighting, based on light-emitting diode (LED), on the acclimation of pre-sprouted sugarcane seedlings in a protected environment. The experimental design was completely randomized, consisting of three supplemental LED lighting systems, with light proportions of 90% red + 10% blue (R:B 90/10), 80% red + 20% blue (R:B 80/20) and 70% red + 30% blue (R:B 70/30), and a control, with natural solar radiation, with 5 replicates. Multivariate principal component analysis was used based on the matrix of correlation between all variables (meteorological, physiological and biometric). It was found that the different LED lighting systems increased the photosynthetically active radiation; however, until 20 days after planting, the seedlings were little influenced by the supplemental lighting systems. At the end of the acclimation period, the R:B 80/20 lighting system was the most associated with the growth and size of sugarcane seedlings.

RESUMO A cana-de-açúcar é uma gramínea que se destaca mundialmente na produção de etanol. O Brasil é o maior produtor mundial e líder na exportação, responsável por mais de 50% dos produtos derivados que são comercializados no mundo. Objetivou-se averiguar a influência de malhas fotosseletivas nas variáveis micrometeorológicas e na brotação de mudas pré-brotadas de cana-de-açúcar. A pesquisa foi realizada em ambiente protegido na Universidade Federal Rural de Pernambuco, em delineamento inteiramente casualizado. As mudas da cultivar RB92579 foram obtidas pela técnica de produção de mudas pré-brotadas. O ambiente protegido foi dividido em quatro módulos, correspondentes aos tratamentos: coberto com plástico polietileno de baixa densidade anti-UV + malha ultranet vermelha Solpack®, + malha branca Solpack®, + malha freshnet Solpack® e sem malha de sombreamento. Foram registrados os dados micrometeorológicos de temperatura do ar e temperatura do substrato em cada módulo. Foram calculadas a primeira contagem de emergência, o índice de velocidade de brotação e a porcentagem de brotação. Foi utilizada a análise multivariada de componentes principais para verificar a associação entre os módulos de cultivo e as variáveis micrometeorológicas e de brotação das mudas. A temperatura do ar no ambiente protegido foi 8.7% maior em relação ao ambiente externo. A malha branca proporcionou 78,93% de brotação. A temperatura do substrato acima de 30,4 °C favoreceu a brotação das mudas. Os módulos com malha branca e ultranet vermelha favoreceram a brotação das mudas.

ABSTRACT Sugarcane is a grass species that stands out worldwide in the production of ethanol. Brazil is the world’s largest producer and leader in exports, responsible for more than 50% of the products that are marketed worldwide. The objective of this study was to investigate the effect of photo-selective nets on micrometeorological variables and on sprouting of pre-sprouted sugarcane seedlings. The experiment was carried out in a protected environment at Universidade Federal Rural de Pernambuco - UFRPE, in a completely randomized design. Seedlings of cultivar RB92579 were obtained by the technique of production of pre-sprouted seedlings. The protected environment was divided into four modules corresponding to the treatments: covered with anti-UV low-density polyethylene plastic: + Solpack® red ultranet net, + Solpack® white net, + Solpack® freshnet net and without shade net. Micrometeorological data of air temperature and substrate temperature were recorded in each module. The first count of emergence, sprouting speed index and sprouting percentage were calculated. Principal component analysis was used to verify the association between the cultivation modules and the micrometeorological and sprouting variables of the seedlings. Air temperature in the protected environment was 8.7% higher than that in the external environment. The white net led to sprouting of 78.93%. The substrate temperature above 30.4 °C favored seedling sprouting. The modules with white net and red ultranet net favored seedling sprouting.

RESUMO O Brasil é o maior produtor mundial de cana-de-açúcar (Saccharum officinarum L.), e pesquisas voltadas à propagação têm proporcionado maior qualidade na produção. Objetivou-se averiguar o efeito da variação dos elementos micrometeorológicos na sobrevivência e qualidade de mudas pré-brotadas de cana-de-açúcar. A pesquisa foi realizada em ambiente protegido (UFRPE). As mudas da cultivar RB92579 foram obtidas pela técnica de produção de mudas pré-brotadas. Os ambientes protegidos foram divididos em quatro módulos cobertos com plástico polietileno de baixa densidade + malhas de sombreamento fotosseletivas e um módulo sem malha. Foram registrados os dados micrometeorológicos de radiação solar global e fotossinteticamente ativa, temperatura do ar e do substrato, umidade relativa do ar e o espectro de radiação solar em cada módulo. O experimento foi instalado em delineamento inteiramente casualizado e foi utilizada a análise de componentes principais para verificar a associação entre os módulos de cultivo, as variáveis micrometeorológicas e da cultura. O plástico de polietileno de baixa densidade antiUV + freshnet proporcionou menor transmitância da radiação solar global, maior porcentagem de radiação fotossinteticamente ativa e menor mortalidade de mudas. Temperatura do substrato acima de 30,2 °C ocasionou maior mortalidade de mudas. O maior espectro na faixa do vermelho proporcionou a produção de mudas de qualidade superior. O uso de malha freshnet promoveu condições adequadas para o cultivo de mudas de cana-de-açúcar, permitindo a obtenção de mudas de qualidade superior.

ABSTRACT Brazil is the world’s largest producer of sugarcane (Saccharum officinarum L.) and research aimed at propagation has promoted higher quality in production. The objective of this study was to investigate the effect of the variation of micrometeorological elements on the survival and quality of pre-sprouted sugarcane plantlets. The study was carried out in a protected environment (UFRPE). Plantlets of the cultivar RB92579 were obtained by the technique of production of pre-sprouted plantlets. The protected environments were divided into four modules covered with low-density polyethylene plastic + photo-selective shade nets and one module without shade net. Micrometeorological data of global and photosynthetically active solar radiation, air temperature, substrate temperature, relative humidity and the solar radiation spectrum were recorded in each module. The experiment was conducted in a completely randomized design and the principal component analysis was used to verify the association between the cultivation modules, micrometeorological variables and crop variables. Anti-UV low-density polyethylene plastic + freshnet led to lower transmittance of global solar radiation, higher percentage of photosynthetically active radiation and lower plantlet mortality. Substrate temperature above 30.2 °C resulted in higher plantlet mortality. Larger spectrum in the red range led to the production of better quality plantlet. The use of freshnet shade net promoted adequate conditions for the cultivation of sugarcane plantlets and allows obtaining better quality plantlets.

ABSTRACT: In Brazil, the conventional center pivot is widely used for irrigation of agricultural crops and its use has grown continuously. However, when improperly managed, it facilitates the development of diseases in all parts of the plant, with a direct effect on productivity, besides favoring losses of water by evaporation. The drip may be an alternative, since it minimizes the losses and does not wet the aerial parts of the plants, thereby reducing the incidence of diseases. A new system called localized mobile drip irrigation (IRGMO) is being developed in an attempt to combine the practicality and rusticity of the center pivot with the efficiency and water savings of the dripping irrigation systems. This fusion system is the central pivot with drip irrigation system for water distribution in the soil surface. This study aims to present a calculation methodology for the design of IRGMO system and compare it with conventional systems. It is concluded that this methodology allows the design of the IRGMO and that this new technology allows a savings of approximately 99% in a number of drip tubes compared to the conventional system with fixed drip irrigation lines in the field.

ABSTRACT The tariff flags on Brazil came into force in January 2015, applied to all electrical distribution agents of the national interconnected system (SIN) and all final consumers are being charged for this new model. Given this, the cost of electricity in irrigation suffered representative additions involving searches of alternatives, such as the use of diesel engines. This study aimed to analyze the costs and the total annual costs of pumping with diesel and electric operation in 3 regions of Brazil, considering the application of the tariff flags. We concluded that the Southeast region (SE) features an hourly cost of electricity above the Central-West (CO) and the Northeast (NE) regions at any adopted tariff, regardless of the time of pumping and the use of diesel engines in irrigation is feasible in terms of distances from the electrical grid that can range from 2.8 to 72.4 km, the first being the most favorable condition in the Southeast with the operation of 4 months per year with fertirrigation, in conventional tariff and red flag is the less favorable in the Northeast with 10 months/year operation with/without fertirrigation, in bohemia blue and green flag tariff.

Neste estudo foi analisada uma população do marsupial neotropical Didelphis albiventris (Lund, 1840), em um fragmento florestal urbano, e foram analisados aspectos da estrutura da população, e a influência do sexo e da idade em duas variáveis relativas ao uso do hábitat - Área de Vida Diária (MCP) e Intensidade de Uso do Hábitat (UI), obtidas com a técnica do carretel de rastreamento. Foram estudados 49 indivíduos marcados, dos quais 20 eram machos e 29 eram fêmeas. Dos animais adultos, não foi encontrado qualquer dimorfismo sexual. De 40 indivíduos rastreados com carretel (16 machos, 24 fêmeas), diferenças significativas no MCP foram encontradas, sendo que os indivíduos adultos apresentaram tamanhos médios maiores que os sub-adultos. Quanto à UI, diferenças significativas foram observadas também relacionadas à idade. Não foram encontradas diferenças entre sexos com relação ao MCP e IU. Além dos fatores analisados, as variáveis relativas ao uso do hábitat possivelmente são influenciadas por outros fatores, especialmente aqueles relacionados ao estado de conservação do fragmento.

A population of the Neotropical marsupial Didelphis albiventris (Lund, 1840) living in an urban forest fragment was studied. Population structure and the influence of sex and age on two variables related to habitat use (Daily home range - MCP and Habitat use intensity - UI) obtained by the spool-and-line technique were analysed. There were 20 males and 29 females studied (N = 49). No sexual dimorphism was apparent in adult individuals. There were 16 males and 24 females tracked using the spool-and-line device. There were significant differences found in the mean size of the daily home range, which was greater in adults than in sub-adults. Regarding the habitat use intensity there were also significant differences related to age. There were no significant differences in MCP and UI related to the sex of the individuals. Besides the analyzed factors, the variables related to habitat use are possibly influenced by other factors, especially, the ones related to the conservation status of the fragment.